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Amazon dark earth

Micheal Palace has been kind enough to share the attached poster with some of his initial work detecting Amazonian dark earths (called ABE in the poster) using satellite images from NASA's Hyperion spectrum scans of the Amazon region.

The team of scientists working on the technology have been correlating archeological evidence of the Dark Earths (ABE) and the Hyperion scans of the same areas to see if they can find a way to reliably use the scans to detect other areas of Amazonian Dark Earths. Ultimately, they'd like to use the Hyperion data to find the extent of the dark earths in the Amazon basin, and be able to provide archeologist with the statistical likelihood that there are actually ancient dark earths in the areas indicated by the scans.

After the conference, about 50 participants flew to Manaus and boarded the well-appointed riverboat, Helios Gabriel on Thursday evening September 16th, 2010. There were plenty of opportunities to carry on discussions begun at the conference.

The objective of the first day was to visit small farmers growing crops on Terra Preta sites at the Costa Naranjal, the

"Terra Preta de Indio" (Amazonian Dark Earths; earlier also called "Terra Preta do Indio" or Indian Black Earth) is the local name for certain dark earths in the Brazilian Amazon region. These dark earths occur, however, in several countries in South America and probably beyond. They were most likely created by pre-Columbian Indians from 500 to 2500 years B.P. and abandoned after the invasion of Europeans (Smith, 1980; Woods et al., 2000). However, many questions are still unanswered with respect to their origin, distribution, and properties.

Above ground, rainforests like the Amazon basin flourish as biological hot spots with exuberant growth and a riot of plant and animal species.

But the red and yellow soils below are notoriously poor in nutrients and organic matter. Once the lush vegetation is cleared, the heavy rains and tropical sun quickly decompose even that small reservoir.

Except not in thousands of patches dotted along the Amazon River and its tributaries, where dark, friable soil extends metres deep, fertile in nutrients and organic material. In total, an area the size of France may be covered by this Indian black earth, called terra preta do Indio in Portuguese.

"The textbooks say it shouldn't be there. That's justification enough for me to explore why it is there," says Johannes Lehmann, a Cornell University professor specializing in the chemistry and geology of soils.